For a very simple reason that time flies rather quickly.
I remember when I first saw the announcement for The Hobbit. "Huh...it's gonna take forever to get to the end of 2012..."
Before I knew it, I was sitting there in the theater and watching it.

. . . which contains a few old video games and some 13-14 year old Legos.
Seeing a SW movie in a theater is something I've never done before. Neither is going to a midnight premier, and I'm looking forward to both. I wouldn't give that up, even to see the movie in advance.